Possible Exploitable Flaw Found in New Firefox
Browser Version

December
15th 2005

Firefox logo

Mozilla
Foundation has issued a security advisory for its new Firefox
version 1.5 browser. This is what happens. The browser will hang
when the history includes a real long page title / location (like
2.5 million characters for instance). The browser will hang when
processing the long file.

The only way to
correct this is to clear the Firefox history file (history.dat).
Researchers at PacketStorm security group has warned that the bug
can result in hackers gaining control of a system, not just a denial
of service (DoS) attack.

Mozilla claims
there is no evidence of a security risk. According to TechTree the
advisory says that “there is no risk to users or their computers,
beyond the browser's temporary un-responsiveness at start-up.”
Mozilla adds that there is no evidence found to back-up claims that
variants of the DoS attack can cause an exploitable crash.

The problem
appears to be easy to fix, according to Mozilla. If the history.dat
file exceeds 10.5MB the system will appear to freeze. According to
Silicon.com the system is not really frozen, but just takes a lot of
time to clear the buffer.

The security
advisory issued Sunday did acknowledge concerns that can cause a
buffer overflow error. Wednesday the first exploit code for this
vulnerability was published. This non-critical error (according to
Mozilla) can be fixed by “clearing the browser history”.